Global food prices shot up last month due to extreme weather conditions, according to the Food and Agriculture Organisation (FAO) of the United Nations.

The price spike has raised the spectre of a food crisis like the one in 2007-2008 that badly hurt the world's poorest.

Unveiling a report on Thursday, the FAO said its food index rose 6 per cent in July from June after dropping for three consecutive months.

The rebound of the index, which measures the monthly change in the international prices of staple foods, was driven by a sharp rise in grain and sugar prices.

Extensive drought in the United States pushed up maize prices by almost 23 per cent in July, said the Rome-based UN agency. The US is the world's No. 1 exporter of maize.

During the same period, wheat prices surged 19 per cent, as dry weather worsened production prospects in the Russian Federation.

July also saw a sharp increase in the price of sugar. The upturn, ending a steady fall since March, was triggered by untimely rains in Brazil, the world's largest sugar exporter. Poor rains in Australia also contributed, the FAO said.

A drought-like situation in some states of India, one of the world's largest food producers and consumers, may dent the production prospects of grains, sugarcane, pulses and oil seeds and cotton this season.

A piece of good news is that international rice prices remain mostly unchanged, as do dairy prices. The FAO's meat price index also fell.

The UN body closely monitors global food prices, as the cost of food is of constant concern for the poor. Hikes in recent years have led to riots in some countries.

Meanwhile, as a food-importing country, Bangladesh is alarmed by the looming crisis.

Making things gloomier is the lack of enough rain threatening a setback in domestic production of Aman rice this year.

"We are worried at the below-normal rainfall at home this year," said Bangladesh Food Minister Abdur Razzaque.

He added that his ministry had sought weather projections and relevant data from the meteorological office and the Water Development Board (WDB) to assess the situation.

The minister was talking to The Daily Star on Tuesday, hours after the International Food Policy Research Institute (IFPRI) issued a statement warning that the most severe and extensive drought in the US since the 1950s was adversely affecting production of maize and soybeans, driving up prices of agricultural products.

Considering the gravity of the situation, the Washington-based food policy think-tank asked for a halt to biofuel production from maize.

According to the Economic Research Service of the US Department of Agriculture, about 40 per cent of maize and soybean, and 44 per cent of livestock are produced in areas experiencing severe drought.

The IFPRI statement read, "Prices of maize and soybeans have already started to rise rapidly and could increase further depending on the degree of severity and extent of the drought. In the past two months alone, US export prices for maize and soybean increased by 30 and 19 per cent respectively, with prices of both crops reaching record highs."

Abdur Razzaque said that in a little over a month, Bangladesh's import price for wheat rose from US$280 to $335 a tonne.

"We'll be seriously affected if US drought situation pushes further, particularly in the prices of soybean oil and poultry feed (prepared from de-oiled soybean meal)."

Bangladesh is the 7th largest importer of soybean oil, and along with Brazil and India, the US is also a source country for its edible oil supplies, Razzaque added.

The food minister said if the pattern of less-than-normal rainfall persisted, it would have a negative bearing on the rain-fed Aman, now in the fields.

Met office figures show -- except for Chittagong and Rangpur -- all divisions in the country experienced less than average rainfall last month. Rainfall in Rajshahi was 33 per cent less than the average, in Sylhet 31 per cent, Dhaka 22 per cent, Barisal 21 per cent and in Khulna 6 per cent less.

Farmers in the country's rice-rich northern region are awaiting a good shower so that they don't require any supplementary irrigation for the Aman production.

Arifuzzaman Bhuiyan, a sub-divisional engineer at the WDB Flood Forecasting and Warning Centre, told this correspondent that the country experienced less than normal rainfall both in June and July.

Explaining the weather charts from the Met office, Arifuzzaman said there was no prospect of a good rainfall in the first half of this month either. He, however, pinned high hopes on the prospect of a downpour in the later part of the month.